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Whaley-Mayda L, Guha A, Tokmakoff A. Multimode vibrational dynamics and orientational effects in fluorescence-encoded infrared spectroscopy. II. Analysis of early-time signals. J Chem Phys 2023; 159:194202. [PMID: 37966136 DOI: 10.1063/5.0171946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 10/19/2023] [Indexed: 11/16/2023] Open
Abstract
Developing fluorescence-encoded infrared (FEIR) vibrational spectroscopy for single-molecule applications requires a detailed understanding of how the molecular response and external experimental parameters manifest in the detected signals. In Paper I [L. Whaley-Mayda, A. Guha, and A. Tokmakoff, J. Chem. Phys. 159, 194201 (2023)] we introduced a nonlinear response function theory to describe vibrational dynamics, vibronic coupling, and transition dipole orientation in FEIR experiments with ultrashort pulses. In this second paper, we apply the theory to investigate the role of intermode vibrational coherence, the orientation of vibrational and electronic transition dipoles, and the effects of finite pulse durations in experimental measurements. We focus on measurements at early encoding delays-where signal sizes are largest and therefore of most value for single-molecule experiments, but where many of these phenomena are most pronounced and can complicate the appearance of data. We compare experiments on coumarin dyes with finite-pulse response function simulations to explain the time-dependent behavior of FEIR spectra. The role of the orientational response is explored by analyzing polarization-dependent experiments and their ability to resolve relative dipole angles in the molecular frame. This work serves to demonstrate the molecular information content of FEIR experiments, and develop insight and guidelines for their interpretation.
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Affiliation(s)
- Lukas Whaley-Mayda
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Abhirup Guha
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
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2
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Brixner T, Mueller S, Müller A, Knote A, Schnepp W, Truman S, Vetter A, von Mammen S. femtoPro: virtual-reality interactive training simulator of an ultrafast laser laboratory. APPLIED PHYSICS. B, LASERS AND OPTICS 2023; 129:78. [PMID: 37152905 PMCID: PMC10148635 DOI: 10.1007/s00340-023-08018-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/12/2023] [Indexed: 05/09/2023]
Abstract
The huge field of optics and photonics research and development is in constant demand of well-trained experts. However, it is challenging to teach efficiently the setup process of complicated optical experiments due to limited hardware availability and eye-safety concerns, in particular, in the case of femtosecond lasers. We have developed an interactive simulation of an ultrafast laser laboratory ("femtoPro") for teaching and training, implementing physical models for the calculation and visualization of Gaussian laser beam propagation, ultrashort optical pulses, their modulation by typical optical elements, and linear as well as nonlinear light-matter interaction. This facilitates the setup and simulated measurement procedure, in virtual reality (VR) and at real-time speeds, of various typical optical arrangements and spectroscopy schemes such as telescopes, interferometers, or pulse characterization. femtoPro can be employed to supplement academic teaching in connection with regular courses in optics or spectroscopy, to train future scientists and engineers in the field of (ultrafast) optics in practical skills, to communicate to other researchers how to set up and align a particular experiment, to "test-build" and simulate new designs of optical setups, to simulate ultrafast spectroscopy data, to offer practical exercises to high-school students, and to reach out to the general public.
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Affiliation(s)
- Tobias Brixner
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Stefan Mueller
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Andreas Müller
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Games Engineering, Institut für Informatik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Andreas Knote
- Games Engineering, Institut für Informatik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Wilhelm Schnepp
- Games Engineering, Institut für Informatik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Samuel Truman
- Games Engineering, Institut für Informatik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Anne Vetter
- Games Engineering, Institut für Informatik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Sebastian von Mammen
- Games Engineering, Institut für Informatik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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3
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Duan R, Mastron JN, Song Y, Kubarych KJ. Direct comparison of amplitude and geometric measures of spectral inhomogeneity using phase-cycled 2D-IR spectroscopy. J Chem Phys 2021; 154:174202. [PMID: 34241049 DOI: 10.1063/5.0043961] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Two-dimensional infrared (2D-IR) spectroscopy provides access to equilibrium dynamics with the extraction of the frequency-fluctuation correlation function (FFCF) from the measured spectra. Several different methods of obtaining the FFCF from experimental spectra, such as the center line slope (CLS), ellipticity, phase slope, and nodal line slope, all depend on the geometrical nature of the 2D line shape and necessarily require spectral extent in order to achieve a measure of the FFCF. Amplitude measures, on the other hand, such as the inhomogeneity index, rely only on signal amplitudes and can, in principle, be computed using just a single point in a 2D spectrum. With a pulse shaper-based 2D-IR spectrometer, in conjunction with phase cycling, we separate the rephasing and nonrephasing signals used to determine the inhomogeneity index. The same measured data provide the absorptive spectrum, needed for the CLS. Both methods are applied to two model molecular systems: tungsten hexacarbonyl (WCO6) and methylcyclopentadienyl manganese tricarbonyl [Cp'Mn(CO)3, MCMT]. The three degenerate IR modes of W(CO)6 lack coherent modulation or noticeable intramolecular vibrational redistribution (IVR) and are used to establish a baseline comparison. The two bands of the MCMT tripod complex include intraband coherences and IVR as well as likely internal torsional motion on a few-picosecond time scale. We find essentially identical spectral diffusion, but faster, non-equilibrium dynamics lead to differences in the FFCFs extracted with the two methods. The inhomogeneity index offers an advantage in cases where spectra are complex and energy transfer can mimic line shape changes due to frequency fluctuations.
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Affiliation(s)
- Rong Duan
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, Michigan 48109, USA
| | - Joseph N Mastron
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, Michigan 48109, USA
| | - Yin Song
- Department of Physics, University of Michigan, 430 Church Ave., Ann Arbor, Michigan 48109, USA
| | - Kevin J Kubarych
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, Michigan 48109, USA
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4
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Huber L, Maehrlein SF, Wang F, Liu Y, Zhu XY. The ultrafast Kerr effect in anisotropic and dispersive media. J Chem Phys 2021; 154:094202. [PMID: 33685130 DOI: 10.1063/5.0037142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The ultrafast optical Kerr effect (OKE) is widely used to investigate the structural dynamics and interactions of liquids, solutions, and solids by observing their intrinsic nonlinear temporal responses through nearly collinear four-wave mixing. Non-degenerate mixing schemes allow for background free detection and can provide information on the interplay between a material's internal degrees of freedom. Here, we show a source of temporal dynamics in the OKE signal that is not reflective of the internal degrees of freedom but arises from a group index and momentum mismatch. It is observed in two-color experiments on condensed media with sizable spectral dispersion, a common property near an optical resonance. In particular, birefringence in crystalline solids is able to entirely change the character of the OKE signal via the off-diagonal tensor elements of the nonlinear susceptibility. We develop a detailed description of the phase-mismatched ultrafast OKE and show how to extract quantitative information on the spectrally resolved birefringence and group index from time-resolved experiments in one and two dimensions.
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Affiliation(s)
- Lucas Huber
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| | | | - Feifan Wang
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| | - Yufeng Liu
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| | - X-Y Zhu
- Department of Chemistry, Columbia University, New York, New York 10027, USA
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Pres S, Kontschak L, Hensen M, Brixner T. Coherent 2D electronic spectroscopy with complete characterization of excitation pulses during all scanning steps. OPTICS EXPRESS 2021; 29:4191-4209. [PMID: 33771004 DOI: 10.1364/oe.414452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 12/26/2020] [Indexed: 06/12/2023]
Abstract
Coherent two-dimensional (2D) electronic spectroscopy has become a standard tool in ultrafast science. Thus it is relevant to consider the accuracy of data considering both experimental imperfections and theoretical assumptions about idealized conditions. It is already known that chirped excitation pulses can affect 2D line shapes. In the present work, we demonstrate performance-efficient, automated characterization of the full electric field of each individual multipulse sequence employed during a 2D scanning procedure. Using Fourier-transform spectral interferometry, we analyze how the temporal intensity and phase profile varies from scanning step to scanning step and extract relevant pulse-sequence parameters. This takes into account both random and systematic variations during the scan that may be caused, for example, by femtosecond pulse-shaping artifacts. Using the characterized fields, we simulate and compare 2D spectra obtained with idealized and real shapes obtained from an LCD-based pulse shaper. Exemplarily, we consider fluorescence of a molecular dimer and multiphoton photoemission of a plasmonic nanoslit. The deviations from pulse-shaper artifacts in our specific case do not distort strongly the population-based multidimensional data. The characterization procedure is applicable to other pulses-shaping technologies or excitation geometries, including also pump-probe geometry with multipulse excitation and coherent detection, and allows for accurate consideration of realistic optical excitation fields at all inter-pulse time-delays.
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Zhu R, Yue S, Li H, Leng X, Wang Z, Chen H, Weng Y. Correction of spectral distortion in two-dimensional electronic spectroscopy arising from the wedge-based delay line. OPTICS EXPRESS 2019; 27:15474-15484. [PMID: 31163743 DOI: 10.1364/oe.27.015474] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/07/2019] [Indexed: 06/09/2023]
Abstract
Unlike the probe wavelength, which is spectrally resolved by monochromator, the excitation wavelength in two-dimensional electronic spectroscopy is retrieved by means of Fourier transform of the interference signal introduced by the coherence delay time between the first and second excitation laser pulses. Hence, the calibration of delay lines would determine its accuracy. In this work, we showed that an inaccurate calibration factor of wedge-based delay line would result in a global peak shift and asymmetric spectral twists along the excitation axis. Both theoretical analysis and experiments have shown that such spectral distortions can be corrected by an accurately predetermined calibration factor. The relative accuracy of calibration factor reaches 3 × 10-5 in our setup. The dispersion effect of wedges also has been considered for the broadband excitation.
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Gururangan K, Harel E. Coherent and dissipative quantum process tensor reconstructions in two-dimensional electronic spectroscopy. J Chem Phys 2019; 150:164127. [PMID: 31042925 DOI: 10.1063/1.5082165] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A major goal of time-resolved spectroscopy is to resolve the dynamical processes that follow photoexcitation. This amounts to identifying all the quantum states involved and the rates of population transfer between them. Unfortunately, such quantum state and kinetic reconstructions are ambiguous using one-dimensional methods such as transient absorption even when all the states of the system are fully resolved. Higher-dimensionality methods like two-dimensional spectroscopy lift some of the ambiguity, but unless the spectral features are well-separated, current inversion methods generally fail. Here, we show that, using both coherence and population signals of the nonlinear response, it is indeed possible to accurately extract both static and dynamic information from the 2D spectrum even when features are highly congested. Coherences report on the positions of the vibronic states of the system, providing a useful constraint for extracting the full kinetic scheme. We model time-resolved 2D photon echo spectra using a sum-over-states approach and show in which regimes the Hamiltonian and kinetic schemes may be recovered. Furthermore, we discuss how such algorithms may be applied to experimental data and where some of the underlying assumptions may fail. The ability to systematically extract the maximal information content of multidimensional spectroscopic data is an important step toward utilizing the full power of these techniques and elucidating the structure and dynamics of increasingly complex molecular systems.
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Affiliation(s)
- Karthik Gururangan
- Department of Materials Science and Engineering, Northwestern University, 2200 Campus Drive, Evanston, Illinois 60208, USA
| | - Elad Harel
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA
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8
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Daley KR, Kubarych KJ. An “Iceberg” Coating Preserves Bulk Hydration Dynamics in Aqueous PEG Solutions. J Phys Chem B 2017; 121:10574-10582. [DOI: 10.1021/acs.jpcb.7b08030] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kimberly R. Daley
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, Michigan 48109, United States
| | - Kevin J. Kubarych
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, Michigan 48109, United States
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9
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Yan TM, Fresch B, Levine RD, Remacle F. Information processing in parallel through directionally resolved molecular polarization components in coherent multidimensional spectroscopy. J Chem Phys 2015; 143:064106. [DOI: 10.1063/1.4928066] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Tian-Min Yan
- Department de Chimie, B6c, Université de Liège, B4000 Liège, Belgium
| | - Barbara Fresch
- Department de Chimie, B6c, Université de Liège, B4000 Liège, Belgium
| | - R. D. Levine
- The Fritz Haber Research Center for Molecular Dynamics, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- Crump Institute for Molecular Imaging and Department of Molecular and Medical Pharmacology, David Geffen School of Medicine and Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA
| | - F. Remacle
- Department de Chimie, B6c, Université de Liège, B4000 Liège, Belgium
- The Fritz Haber Research Center for Molecular Dynamics, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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10
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Spencer AP, Li H, Cundiff ST, Jonas DM. Pulse Propagation Effects in Optical 2D Fourier-Transform Spectroscopy: Theory. J Phys Chem A 2015; 119:3936-60. [DOI: 10.1021/acs.jpca.5b00001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Austin P. Spencer
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Hebin Li
- JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440, United States
- Department
of Physics, Florida International University, Miami, Florida 33199, United States
| | - Steven T. Cundiff
- JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440, United States
| | - David M. Jonas
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
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11
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Kitney-Hayes KA, Ferro AA, Tiwari V, Jonas DM. Two-dimensional Fourier transform electronic spectroscopy at a conical intersection. J Chem Phys 2014; 140:124312. [DOI: 10.1063/1.4867996] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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12
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Milota F, Lincoln CN, Hauer J. Precise phasing of 2D-electronic spectra in a fully non-collinear phase-matching geometry. OPTICS EXPRESS 2013; 21:15904-15911. [PMID: 23842377 DOI: 10.1364/oe.21.015904] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report an experimental design for two-dimensional electronic spectroscopy (2D-ES) that avoids the need to measure notoriously weak pump-probe spectra. Retaining a fully non-collinear folded boxcar geometry, the described layout replaces pump-probe with heterodyned transient grating (het-TG). The absorptive component of the het-TG signal is measured directly, following a straightforward optimization routine. The use of het-TG achieves an improvement in signal to noise ratio by almost two orders of magnitude. As a result, 2D-ES-signals down to 0.5% can be clearly resolved.
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Affiliation(s)
- Franz Milota
- Photonics Institute, Vienna University of Technology, Gusshausstrasse 27, 1040 Vienna, Austria
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13
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Rock W, Li YL, Pagano P, Cheatum CM. 2D IR spectroscopy using four-wave mixing, pulse shaping, and IR upconversion: a quantitative comparison. J Phys Chem A 2013; 117:6073-83. [PMID: 23687988 DOI: 10.1021/jp312817t] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Recent technological advances have led to major changes in the apparatuses used to collect 2D IR spectra. Pulse shaping offers several advantages including rapid data collection, inherent phase stability, and phase-cycling capabilities. Visible array detection via upconversion allows the use of visible detectors that are cheaper, faster, more sensitive, and less noisy than IR detectors. However, despite these advantages, many researchers are reluctant to implement these technologies. Here we present a quantitative study of the S/N of 2D IR spectra collected with a traditional four-wave mixing (FWM) apparatus, with a pulse shaping apparatus, and with visible detection via upconversion to address the question of whether weak chromophores at low concentrations are still accessible with such an apparatus. We find that the enhanced averaging capability of the pulse shaping apparatus enables the detection of small signals that would be challenging to measure even with the traditional FWM apparatus, and we demonstrate this ability on a sample of cyanylated dihydrofolate reductase.
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Affiliation(s)
- William Rock
- Department of Chemistry and Optical Science and Technology Center, University of Iowa, Iowa City, Iowa 52242, USA
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14
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Li H, Spencer AP, Kortyna A, Moody G, Jonas DM, Cundiff ST. Pulse Propagation Effects in Optical 2D Fourier-Transform Spectroscopy: Experiment. J Phys Chem A 2013; 117:6279-87. [PMID: 23565590 DOI: 10.1021/jp4007872] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Hebin Li
- JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440, United States
| | - Austin P. Spencer
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado
80309-0215, United States
| | - Andrew Kortyna
- JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440, United States
- Department of Physics, Lafayette College, Easton, Pennsylvania 18042, United States
| | - Galan Moody
- JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440, United States
- Department of Physics, University of Colorado, Boulder, Colorado
80309-0440, United States
| | - David M. Jonas
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado
80309-0215, United States
| | - Steven T. Cundiff
- JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440, United States
- Department of Physics, University of Colorado, Boulder, Colorado
80309-0440, United States
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15
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King JT, Baiz CR, Kubarych KJ. Solvent-dependent spectral diffusion in a hydrogen bonded "vibrational aggregate". J Phys Chem A 2011; 114:10590-604. [PMID: 20831231 DOI: 10.1021/jp106142u] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Two-dimensional infrared spectroscopy (2DIR) is used to measure the viscosity-dependent spectral diffusion of a model vibrational probe, Mn(2)(CO)(10) (dimanganese decacarbonyl, DMDC), in a series of alcohols with time scales ranging from 2.67 ps in methanol to 5.33 ps in 1-hexanol. Alcohol-alkane solvent mixtures were found to produce indistinguishable linear IR spectra, while still demonstrating viscosity-dependent spectral diffusion. Using a vibrational exciton model to characterize the inhomogeneous energy landscape, several analogies emerge with multichromophoric electronic systems, such as J-aggregates and light-harvesting protein complexes. An excitonic, local vibrational mode Hamiltonian parametrized to reproduce the vibrational structure of DMDC serves as a starting point from which site energies (i.e., local carbonyl frequencies) are given Gaussian distributed disorder. The model gives excellent agreement with both the linear IR spectrum and the inhomogeneous widths extracted from 2DIR, indicating the system can be considered to be a "vibrational aggregate." This model naturally leads to exchange narrowing due to disorder-induced exciton localization, producing line widths consistent with our 1D and 2D measurements. Further, the diagonal disorder alone effectively reduces the molecular symmetry, leading to the appearance of Raman bands in the IR spectrum in accord with the measurements. Here, we show that the static inhomogeneity of the excitonic model with disorder successfully captures the essential details of the 1D spectrum while predicting the degree of IR activity of forbidden modes as well as the inhomogeneous widths and relative magnitudes of the transition moments.
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Affiliation(s)
- John T King
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, USA
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